DESCRIPTION: The goal of this project is to study the developmental profile in mouse of genes that map within the VCFS critical region. Knock-out and deletion mice that have been generated by Project III will be characterized and include Gscl -/- mice, Arvcf-/- mice, and Idd-Arvcf deletion mice. The principal investigator will compare the developmental expression profile between normal mice embryos and the knock-out/deletion mice using two techniques; DNA microarrays and cDNA representational difference analysis. The investigator will use a similar strategy to characterize knock-out mice that delete non-chromosome 22 genes but present with abnormalities similar to VCFS. These mice include the endothelin-A receptor knock-out mouse and the Hoxa-3 knock-out mouse. Finally, the investigator will continue to characterize the developmental profile of mouse genes that are orthologous to genes identified in Project I.